Wood-grinder



'(No Model.) l

. S. M. ALLEN. v WoodGrinder for Making Paper Pulp Patenied Sept, 21, ,1880.

To all whom itoimy concern: 1

UNITED. STATES PATENT "OF ICE,

STEPHEN M; ALLEN, OF DUXBURY, MASSACHUSETTS.

W QOD-G R IND ER Fo'R MAKlNGPA PER-PU LP.

SPECIFICATION forming part of Letters Patent No. 232331, dated September 21, 1880..

Application filed March 18, 1880. (N model.)

' Be itknown' that 1,-STEPHEN M. ALLEN, of Duxhury, State otMassachnsetts, have invented anew and useful Improvement in ced-G rinders for Making: Paper-Pulp, which invention is fully set forth in the followingspeeification. p

This invention relates toartificial-stone or. emery grinders for reducing wood or-other fiber to pulp for paper-mak ng or other pur- "pose, inwhich the abradingor grinding surdated November 25, 1879-.

face of the whole body of the grinder'isformed insect-ions, which are separately molded and compressed and then united; and the'preseilt invention has reference more particularly to the'grimlers termed of a series of compara- Lively thin disks confined upon a-suitable shaft, as shown in my Patent No. 221,993,

-The invention consists inthe construction of the disks-constituting the sections of a cylindrical or conical grinder, so that their lines of junction do not extend directly around the grinder ina plane perpendieularto the axis of the grinder, but are broken by the over}, lapping of adjacentdisks. This is best ett'eeted by making the line's'ru'n obliquely or diagonally with reference to such planer a In using a cylinder or grinderin which the iunctions between the sections extend directly around the same, wood becomes creased or furrowed, so as to leave projections, corresponding to, the joints'betweeuthe ,disks,

which projections'are brokenfofi unground, and, going with the pulp as little lumps, interfere'wit'h the subsequent operations. This objection is completely overcome by my present invention. The disks'arc so formed-that when secured together they break joints,a'nd thes'eams are spiral. The-wood. is in this. way ground oil" evenl'a; and there are no pro- I jectingridges. -Fromthe shape'of the disks,

also, they are pressed more firmlv together and bind each other so that they cannot turn one against theother. v

The following description will enable'those skilled in tllO'iLI'li to which it appertainsto make and. use theinveution, reference being,

had to the accompanying drawings ,'which 1; form a part of this specification.

Figure 1 is a side elevation of a grinder eonstrueted 'in accordance witli said niventioii;

Fig. 2, a longitudinal section, and Fig. 3 a

perspeetiye view, of one of. the disks detached. The grinder, as shown, is composed of end sections or disks, A, and intermediate sections ordisks, A, supported upon a shaft, D','flll(l "clamped together bynuts G. The shape which is or maybe adopted is clearly shown'in'thel dra'wingsf Each disk'," instead of being of equal thickness through'out -has its 'flat sides inclined toward each other, so that the face gradually diminishes from its widest portion in 'ei-th e'r direction 'to theopposite point, wh ere it is narrowest. The inclination of the Ltlat sides in the intermediate sections toward the een'tralflplane is preferably the same for both.

The end pieces, A, naveonlyone oftheir flat sides inclined, the other being perpendicular jto the axis. The disks maybe of different sizes, but are usually from four to six inches in thickness. The thickness should notbe greater than can be thoroughly compacted.

The material is prepared by mixing crushed and granulated emery,eorun'dum, quartz, flint, brother hard stone with a suitable cementing liquid or paste to theconsisteney required for n olding, and is then cast and compressed in molds of snitable'size and-shape;

or disks are partially dried and usually water .proofed, and then dried and turned otf.- The The rollers disks or sections are then placed in position on ashaft or niandrelfllon which 'theyzare secured and'clamped by the nuts (I or by other suitablemeans.

The operation of agrinding-wheel, such as shown, will be readily understood. The wood is presented sidewise, endwise, or in any other position, and the fibersareground off by the abrading-surfaee. Sincethe line of junction v ofthe disks-extends diagonally in short spirals around the cylinder there is no possibility of grinding grooves in the wood; but if the fiber isnot removed at a point opposite any of the dividing-fines-between the sections it is immediatelyreinoved by'contact with the succeeding abrading-surface projecting beyond said point on the one side or the other:

disks-such, for example, as obtained by pass-f mg a number of plauesthrough a cylinder in directions oblique to theaxis. It is not nec- Ditferent forms maybe given to the section- 1 essary, however, that the disks should be of such forms, since their sides need not be flat, the essential features being, first, that the portions of adjacent disks overlap, so as to break joints, and, secondly, as the best form of said arrangement, that the edges are oblique,-

whether in the saine direction or in different directions-for example, zigzag-to the plane perpendicular to. the axis of the cylinder or grinder. It is notnecessary that the disks be of unequal thickness. 'Their opposite sides may be parallel. It is preferred, however, that the sections or disks should be as nearly as possible uniform, and that they should be, as it were, Wedge-shaped, with flat sides, substantially as shown. The number of disks may he even or odd, and is regulated by the length of the cylinder required.

Having now described my said invention 20 and the manner in which the same is or may be carried into died, I desire it to be clearly understood that I do .not limit the invention to the particular construction of the disks indicated in order to effect the desired oblique direction of lines of junction, and also that I do not claimdlrein the construction of a grinder comprising disk-sections, with their edges bounded by lines oblique to the. axis of the cylinder, so that the oblique junction-lines are not parallel, but'extend toward opposite ends of the cylinder, although such a construction is shown in the drawings, nor the use of v interlocking projections on the contiguous ends of the disk-sections, although this is sug gested by the statement that the junctions between the sections may be zigzag, since these special constructions are made subject-matter but a What I do claim, and-desire to secure, is- 1. A grinder composed of disk -sections overlapping at the edges, so as to break joints,

substantially as described.

2. A grinderof artificial stone, emery, or corundum, coriiposed of sections or disks, as described, secured upon a shaft, so that the lines of junction between said sections or disks of 'a separate application for Letters Patent;

around saidgrinder are oblique to planes perpendicular to the axis, substantially as set forth. a I I STEPHEN ALLEN. 

